Secondary, or rechargeable, lithium-based batteries are often used in many stationary and portable devices, such as those encountered in the consumer electronic, automobile, and aerospace industries. The lithium class of batteries has gained popularity for various reasons, including a relatively high energy density, a general nonappearance of any memory effect when compared to other kinds of rechargeable batteries, a relatively low internal resistance, and a low self-discharge rate when not in use. The ability of lithium batteries to undergo repeated power cycling over their useful lifetimes makes them an attractive and dependable power source.
Test cells are often used to study the characteristics (e.g., voltage, impedance, etc.) of lithium-based batteries so that those characteristics may be quantified and improved. In some test cells, a reference electrode is used to help measure the characteristics of the battery. For example, a reference electrode may be added to a test cell to help measure the voltage of a lithium-based battery by providing a potential against which the potentials of the negative electrode and the positive electrode can be measured.